This invention relates to forage harvesters and, more particularly, to a removable recutter screen mounted in the cutterhead housing adjacent to and rearwardly of the generally cylindrical cutterhead to further reduce crop particle size before it is discharged by urging the crop material into engagement with shearing edges of apertures in the screen.
Recutter screens for forage harvesters with cylindrical type cutterheads have been used for a considerable period of time. The use of such screens provides a finer cut of certain crop material then attained by the principal cutting mechanism, thus making the crop more palatable to a livestock and in most instances easier to feed and store.
Generally, in the past, recutter screens have been provided with a relatively large number of closely spaced round apertures with which the cutterhead interacts to recut and force the crop material therethrough. It is also known to use recutter screens with diagonal slot-shaped apertures, as well as square shaped holes. The length of cut effected by the screen varies according to the actual size of the apertures. Usually available are a series of screens each being provided with different size and shape apertures, so that the operator may utilize the screen that best suits crop conditions and size of cut desired.
Recutter screens in the prior art have been provided with apertures all of which are of the same effective size. This permits a uniform length of cut in the resulting crop product being forced through the screen. Any cut crop material that does not exit through the screen in the first pass past the discharge area, is recirculated by the cutterhead. This recirculation of crop material, commonly referred to as "carryover", gives rise to increased power consumption. Carryover also results in an excessive amount of fine particles of crop material due to the second pass through the principal cutting area, as well as the recutting area.